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        <p>Library Version 11.2.5.3</p>
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                Berkeley DB Command Line Utilities
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    <div class="sect1" lang="en" xml:lang="en">
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            <h2 class="title" style="clear: both"><a id="db_recover"></a>db_recover</h2>
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      <pre class="programlisting">db_recover [-cefVv] [-h home] [-P password] [-t [[CC]YY]MMDDhhmm[.SS]]]  </pre>
      <p>
         The <span class="command"><strong>db_recover</strong></span> utility must be run after an unexpected application,
         Berkeley DB, or system failure to restore the database to a consistent
         state.  All committed transactions are guaranteed to appear after
         <span class="command"><strong>db_recover</strong></span> has run, and all uncommitted transactions will be
         completely undone.
    </p>
      <p>
         Note that this utility performs the same action as if the
         environment is opened with the 
         <a class="link" href="envopen.html#envopen_DB_RECOVER">DB_RECOVER</a>
         flag.  If <code class="literal">DB_RECOVER</code> is specified on environment open,
         then use of this utility is not necessary.
    </p>
      <div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
        <h3 class="title">Note</h3>
        <p>
                If the application(s) that use the environment make use of
                any of the following methods:
            </p>
        <table class="simplelist" border="0" summary="Simple list">
          <tr>
            <td>
              <a class="xref" href="envadd_data_dir.html" title="DB_ENV-&gt;add_data_dir()">DB_ENV-&gt;add_data_dir()</a>
            </td>
          </tr>
          <tr>
            <td>
              <a class="xref" href="envset_data_dir.html" title="DB_ENV-&gt;set_data_dir()">DB_ENV-&gt;set_data_dir()</a>
            </td>
          </tr>
          <tr>
            <td>
              <a class="xref" href="envset_lg_dir.html" title="DB_ENV-&gt;set_lg_dir()">DB_ENV-&gt;set_lg_dir()</a>
            </td>
          </tr>
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        <p>
                then in order for this utility to run correctly, you need a
                <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a>
                file which sets the proper paths using the
                <a class="xref" href="add_data_dir_parameter.html" title="add_data_dir">add_data_dir</a>, or
                <a class="xref" href="set_lg_dir_parameter.html" title="set_lg_dir">set_lg_dir</a>
                configuration parameters.
            </p>
      </div>
      <p>
        The options are as follows:
    </p>
      <div class="itemizedlist">
        <ul type="disc">
          <li>
            <p>
                  <span class="bold"><strong>-c</strong></span>
            </p>
            <p>
                Perform catastrophic recovery instead of normal recovery.
            </p>
          </li>
          <li>
            <p>
                 <span class="bold"><strong>-e</strong></span>
            </p>
            <p>
                 Retain the environment after running recovery.  This
                 option will rarely be used unless a <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is
                 present in the home directory.  If a <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is
                 not present, then the regions will be created with default
                 parameter values.
            </p>
          </li>
          <li>
            <p>
                 <span class="bold"><strong>-f</strong></span>
            </p>
            <p>
                 Display a message on the standard output showing the percent of
                 recovery completed.
            </p>
          </li>
          <li>
            <p>
                 <span class="bold"><strong>-h</strong></span>
            </p>
            <p>
                 Specify a home directory for the database environment; by default, the
                 current working directory is used.
            </p>
          </li>
          <li>
            <p>
                 <span class="bold"><strong>-P</strong></span>
            </p>
            <p>
                 Specify an environment password.  Although Berkeley DB utilities
                 overwrite password strings as soon as possible, be aware there may be
                 a window of vulnerability on systems where unprivileged users can see
                 command-line arguments or where utilities are not able to overwrite
                 the memory containing the command-line arguments.
            </p>
          </li>
          <li>
            <p>
                 <span class="bold"><strong>-t</strong></span>
            </p>
            <p>
                 Recover to the time specified rather than to the most current possible
                 date.  The timestamp argument should be in the form
                 <code class="literal">[[CC]YY]MMDDhhmm[.SS]</code> where each pair of letters represents the
                 following:
            </p>
            <div class="itemizedlist">
              <ul type="circle">
                <li>
                  <p>
                        <span class="bold"><strong>CC</strong></span>
                    </p>
                  <p>
                        The first two digits of the year (the century).
                    </p>
                </li>
                <li>
                  <p>
                        <span class="bold"><strong>YY</strong></span>
                    </p>
                  <p>
                        The second two digits of the year. If "YY" is specified, but "CC" is not, a
                        value for "YY" between 69 and 99 results in a "CC" value of 19. Otherwise, a
                        "CC" value of 20 is used.
                    </p>
                </li>
                <li>
                  <p>
                        <span class="bold"><strong>MM</strong></span>
                    </p>
                  <p>
                        The month of the year, from 1 to 12.
                    </p>
                </li>
                <li>
                  <p>
                        <span class="bold"><strong>DD</strong></span>
                    </p>
                  <p>
                        The day of the month, from 1 to 31.
                    </p>
                </li>
                <li>
                  <p>
                        <span class="bold"><strong>hh</strong></span>
                    </p>
                  <p>
                        The hour of the day, from 0 to 23.
                    </p>
                </li>
                <li>
                  <p>
                        <span class="bold"><strong>mm</strong></span>
                    </p>
                  <p>
                        The minute of the hour, from 0 to 59.
                    </p>
                </li>
                <li>
                  <p>
                        <span class="bold"><strong>SS</strong></span>
                    </p>
                  <p>
                        The second of the minute, from 0 to 61.
                    </p>
                </li>
              </ul>
            </div>
            <p>
                 If the "CC" and "YY" letter pairs are not specified, the values
                 default to the current year.  If the "SS" letter pair is not
                 specified, the value defaults to 0.
            </p>
          </li>
          <li>
            <p>
                 <span class="bold"><strong>-V</strong></span>
            </p>
            <p>
                 Write the library version number to the standard output, and exit.
            </p>
          </li>
          <li>
            <p>
                 <span class="bold"><strong>-v</strong></span>
            </p>
            <p>
                Run in verbose mode.
            </p>
          </li>
        </ul>
      </div>
      <p>
         In the case of catastrophic recovery, an archival copy — or
         <span class="emphasis"><em>snapshot</em></span> — of all database files must be
         restored along with all of the log files written since the database
         file snapshot was made. (If disk space is a problem, log files may be
         referenced by symbolic links).  
         
         <span>
            For further information on creating a database snapshot, see
            <a href="../../programmer_reference/transapp_archival.html" class="olink">Archival Procedures</a>.
            For further information on performing recovery, see 
            <a href="../../programmer_reference/transapp_recovery.html" class="olink">Recovery Procedures</a>.
        </span>
    </p>
      <p>
         If the failure was not catastrophic, the files present on the system
         at the time of failure are sufficient to perform recovery.
    </p>
      <p>
         If log files are missing, <span class="command"><strong>db_recover</strong></span> will identify the missing log
         file(s) and fail, in which case the missing log files need to be
         restored and recovery performed again.
    </p>
      <p>
         The <span class="command"><strong>db_recover</strong></span> utility uses a Berkeley DB
         environment (as described for the <span class="bold"><strong>-h</strong></span>
         option, the environment variable 
         <span class="bold"><strong>DB_HOME</strong></span>, or because the utility
         was run in a directory containing a Berkeley DB environment). 
         In order to avoid environment corruption when using a Berkeley DB
         environment, <span class="command"><strong>db_recover</strong></span> should always be given the chance to detach
         from the environment and exit gracefully.  To cause <span class="command"><strong>db_recover</strong></span> to
         release all environment resources and exit cleanly, send it an
         interrupt signal (SIGINT).
    </p>
      <p>
         The <span class="command"><strong>db_recover</strong></span> utility exits 0 on success, and &gt;0 if an error
         occurs.
    </p>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idp55287448"></a>Environment Variables</h3>
            </div>
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        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp55276192"></a>DB_HOME</h4>
              </div>
            </div>
          </div>
          <p>
                          If the <span class="bold"><strong>-h</strong></span> option is not specified and
                          the environment variable DB_HOME is set, it is used as the path of the
                          database home, as described in the
                          <a class="xref" href="envopen.html" title="DB_ENV-&gt;open()">DB_ENV-&gt;open()</a>
                          method.
                     </p>
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